The angle of elevation of a cloud from a point 20 m above a lake is 30

1.	The angle of elevation of a cloud from a point 20 m above a lake is 30 andthe angle of depression of the reflection of cloud in the lake is 60. Height ofthe cloud is given by
Answer» Solution : tan30∘=EC/AD=1/√3(ED=h) =>AD==h√3-----------(1) tan60∘=FD/AD=√3 FD=h+40 AD=h+40/√3---------------(2) h√3=h+40/√3 3h=h+40 2h=40=>h=20m EC=h+20=20+20 =40m

The angle of elevation of a cloud from a point 20 m above a lake is 30 andthe angle of depression of the reflection of cloud in the lake is 60. Height ofthe cloud is given by

Answer»

Solution :

tan30∘=EC/AD=1/√3(ED=h)

=>AD==h√3-----------(1)

tan60∘=FD/AD=√3

FD=h+40

AD=h+40/√3---------------(2)

h√3=h+40/√3

3h=h+40

2h=40=>h=20m

EC=h+20=20+20

=40m